.\" Automatically generated by Pandoc 3.1.3 .\" .\" Define V font for inline verbatim, using C font in formats .\" that render this, and otherwise B font. .ie "\f[CB]x\f[]"x" \{\ . ftr V B . ftr VI BI . ftr VB B . ftr VBI BI .\} .el \{\ . ftr V CR . ftr VI CI . ftr VB CB . ftr VBI CBI .\} .TH "tpm2_duplicate" "1" "" "tpm2-tools" "General Commands Manual" .hy .SH NAME .PP tpm2_duplicate(1) - Duplicates a loaded object so that it may be used in a different hierarchy. .SH SYNOPSIS .PP \f[B]tpm2_duplicate\f[R] [\f[I]OPTIONS\f[R]] .SH DESCRIPTION .PP \f[B]tpm2_duplicate\f[R](1) - This tool duplicates a loaded object so that it may be used in a different hierarchy. The new parent key for the duplicate may be on the same or different TPM or TPM_RH_NULL. .SH OPTIONS .PP These options control the key importation process: .IP \[bu] 2 \f[B]-G\f[R], \f[B]--wrapper-algorithm\f[R]=\f[I]ALGORITHM\f[R]: .RS 2 .PP The symmetric algorithm to be used for the inner wrapper if -U is not used. Supports: .IP \[bu] 2 aes - AES 128 in CFB mode. .IP \[bu] 2 null - none The key algorithm associated with the public parent if -U is used. .RE .IP \[bu] 2 \f[B]-G\f[R], \f[B]--key-algorithm\f[R]=\f[I]ALGORITHM\f[R]: .RS 2 .PP The key algorithm associated with the public parent if -U is used. .RE .IP \[bu] 2 \f[B]-i\f[R], \f[B]--encryptionkey-in\f[R]=\f[I]FILE\f[R]: .RS 2 .PP Specifies the filename of the symmetric key (128 bit data) to be used for the inner wrapper. Valid only when specified symmetric algorithm is not null .RE .IP \[bu] 2 \f[B]-o\f[R], \f[B]--encryptionkey-out\f[R]=\f[I]FILE\f[R]: .RS 2 .PP Specifies the filename to store the symmetric key (128 bit data) that was used for the inner wrapper. Valid only when specified symmetric algorithm is not null and --input-key-file is not specified. The TPM generates the key in this case. .RE .IP \[bu] 2 \f[B]-C\f[R], \f[B]--parent-context\f[R]=\f[I]OBJECT\f[R]: .RS 2 .PP The parent key object. .RE .IP \[bu] 2 \f[B]-U\f[R], \f[B]--parent-public\f[R]=\f[I]FILE\f[R]: .RS 2 .PP Specifies the file path to the public key of the parent object on the destination TPM. This should be a \f[V]TPM2B_PUBLIC\f[R] formatted file. This public key is used for the wrapping of a PEM or DER key which will be exported for a remote TPM. .RE .IP \[bu] 2 \f[B]-k\f[R], \f[B]--private-key\f[R]=\f[I]FILE\f[R]: .RS 2 .PP Specifies the file path to the external private key be encrypted for the remote TPM. This should be a PEM format private key. .RE .IP \[bu] 2 \f[B]-r\f[R], \f[B]--private\f[R]=\f[I]FILE\f[R]: .RS 2 .PP Specifies the file path to save the private portion of the duplicated object. # Protection Details .RE .PP Objects that can move outside of TPM need to be protected (confidentiality and integrity). For instance, transient objects require that TPM protected data (key or seal material) be stored outside of the TPM. This is seen in tools like tpm2_create(1), where the \f[B]-r\f[R] option outputs this protected data. This blob contains the sensitive portions of the object. The sensitive portions of the object are protected by the parent object, using the parent\[cq]s symmetric encryption details to encrypt the sensitive data and HMAC it. .PP In-depth details can be found in sections 23 of: .IP \[bu] 2 https://trustedcomputinggroup.org/wp-content/uploads/TPM-Rev-2.0-Part-1-Architecture-01.38.pdf .PP Notably Figure 20, is relevant, even though it\[cq]s specifically referring to duplication blobs, the process is identical. .PP If the output is from tpm2_duplicate(1), the output will be slightly different, as described fully in section 23. .IP \[bu] 2 \f[B]-u\f[R], \f[B]--public\f[R]=\f[I]FILE\f[R]: .RS 2 .PP Specifies the file path to save the public portion of the duplicated object, if an external key is being duplicated. .RE .IP \[bu] 2 \f[B]-s\f[R], \f[B]--encrypted-seed\f[R]=\f[I]FILE\f[R]: .RS 2 .PP The file to save the encrypted seed of the duplicated object. .RE .IP \[bu] 2 \f[B]-p\f[R], \f[B]--auth\f[R]=\f[I]AUTH\f[R]: .RS 2 .PP The authorization value for the key, optional. .RE .IP \[bu] 2 \f[B]-L\f[R], \f[B]--policy\f[R]=\f[I]FILE\f[R]: .RS 2 .PP The input policy file, optional. .RE .IP \[bu] 2 \f[B]-c\f[R], \f[B]--key-context\f[R]=\f[I]OBJECT\f[R]: .RS 2 .PP The object to be duplicated. .RE .IP \[bu] 2 \f[B]-a\f[R], \f[B]--attributes\f[R]=\f[I]ATTRIBUTES\f[R]: .RS 2 .PP The object attributes, optional. The default for created objects is: .PP \f[V]TPMA_OBJECT_SIGN_ENCRYPT|TPMA_OBJECT_DECRYPT|TPMA_OBJECT_USERWITHAUTH\f[R] .PP Note: If a policy is specified without an auth value then \f[V]TPMA_OBJECT_USERWITHAUTH\f[R] is turned down. .RE .IP \[bu] 2 \f[B]--cphash\f[R]=\f[I]FILE\f[R] .RS 2 .PP File path to record the hash of the command parameters. This is commonly termed as cpHash. NOTE: When this option is selected, The tool will not actually execute the command, it simply returns a cpHash. .RE .SS References .SH Context Object Format .PP The type of a context object, whether it is a handle or file name, is determined according to the following logic \f[I]in-order\f[R]: .IP \[bu] 2 If the argument is a file path, then the file is loaded as a restored TPM transient object. .IP \[bu] 2 If the argument is a \f[I]prefix\f[R] match on one of: .RS 2 .IP \[bu] 2 owner: the owner hierarchy .IP \[bu] 2 platform: the platform hierarchy .IP \[bu] 2 endorsement: the endorsement hierarchy .IP \[bu] 2 lockout: the lockout control persistent object .RE .IP \[bu] 2 If the argument argument can be loaded as a number it will be treat as a handle, e.g.\ 0x81010013 and used directly._OBJECT_. .SH Authorization Formatting .PP Authorization for use of an object in TPM2.0 can come in 3 different forms: 1. Password 2. HMAC 3. Sessions .PP \f[B]NOTE:\f[R] \[lq]Authorizations default to the \f[B]EMPTY PASSWORD\f[R] when not specified\[rq]. .SS Passwords .PP Passwords are interpreted in the following forms below using prefix identifiers. .PP \f[B]Note\f[R]: By default passwords are assumed to be in the string form when they do not have a prefix. .SS String .PP A string password, specified by prefix \[lq]str:\[rq] or it\[cq]s absence (raw string without prefix) is not interpreted, and is directly used for authorization. .SS Examples .IP .nf \f[C] foobar str:foobar \f[R] .fi .SS Hex-string .PP A hex-string password, specified by prefix \[lq]hex:\[rq] is converted from a hexidecimal form into a byte array form, thus allowing passwords with non-printable and/or terminal un-friendly characters. .SS Example .IP .nf \f[C] hex:1122334455667788 \f[R] .fi .SS File .PP A file based password, specified be prefix \[lq]file:\[rq] should be the path of a file containing the password to be read by the tool or a \[lq]-\[rq] to use stdin. Storing passwords in files prevents information leakage, passwords passed as options can be read from the process list or common shell history features. .SS Examples .IP .nf \f[C] # to use stdin and be prompted file:- # to use a file from a path file:path/to/password/file # to echo a password via stdin: echo foobar | tpm2_tool -p file:- # to use a bash here-string via stdin: tpm2_tool -p file:- <<< foobar \f[R] .fi .SS Sessions .PP When using a policy session to authorize the use of an object, prefix the option argument with the \f[I]session\f[R] keyword. Then indicate a path to a session file that was created with tpm2_startauthsession(1). Optionally, if the session requires an auth value to be sent with the session handle (eg policy password), then append a + and a string as described in the \f[B]Passwords\f[R] section. .SS Examples .PP To use a session context file called \f[I]session.ctx\f[R]. .IP .nf \f[C] session:session.ctx \f[R] .fi .PP To use a session context file called \f[I]session.ctx\f[R] \f[B]AND\f[R] send the authvalue mypassword. .IP .nf \f[C] session:session.ctx+mypassword \f[R] .fi .PP To use a session context file called \f[I]session.ctx\f[R] \f[B]AND\f[R] send the \f[I]HEX\f[R] authvalue 0x11223344. .IP .nf \f[C] session:session.ctx+hex:11223344 \f[R] .fi .SS PCR Authorizations .PP You can satisfy a PCR policy using the \[lq]pcr:\[rq] prefix and the PCR minilanguage. The PCR minilanguage is as follows: \f[V]=\f[R] .PP The PCR spec is documented in in the section \[lq]PCR bank specifiers\[rq]. .PP The \f[V]raw-pcr-file\f[R] is an \f[B]optional\f[R] argument that contains the output of the raw PCR contents as returned by \f[I]tpm2_pcrread(1)\f[R]. .PP PCR bank specifiers .SS Examples .PP To satisfy a PCR policy of sha256 on banks 0, 1, 2 and 3 use a specifier of: .IP .nf \f[C] pcr:sha256:0,1,2,3 \f[R] .fi .PP specifying \f[I]AUTH\f[R]. .SH Algorithm Specifiers .PP Options that take algorithms support \[lq]nice-names\[rq]. .PP There are two major algorithm specification string classes, simple and complex. Only certain algorithms will be accepted by the TPM, based on usage and conditions. .SS Simple specifiers .PP These are strings with no additional specification data. When creating objects, non-specified portions of an object are assumed to defaults. You can find the list of known \[lq]Simple Specifiers\[rq] below. .SS Asymmetric .IP \[bu] 2 rsa .IP \[bu] 2 ecc .SS Symmetric .IP \[bu] 2 aes .IP \[bu] 2 camellia .IP \[bu] 2 sm4 .SS Hashing Algorithms .IP \[bu] 2 sha1 .IP \[bu] 2 sha256 .IP \[bu] 2 sha384 .IP \[bu] 2 sha512 .IP \[bu] 2 sm3_256 .IP \[bu] 2 sha3_256 .IP \[bu] 2 sha3_384 .IP \[bu] 2 sha3_512 .SS Keyed Hash .IP \[bu] 2 hmac .IP \[bu] 2 xor .SS Signing Schemes .IP \[bu] 2 rsassa .IP \[bu] 2 rsapss .IP \[bu] 2 ecdsa .IP \[bu] 2 ecdaa .IP \[bu] 2 ecschnorr .IP \[bu] 2 sm2 .SS Asymmetric Encryption Schemes .IP \[bu] 2 oaep .IP \[bu] 2 rsaes .IP \[bu] 2 ecdh .SS Modes .IP \[bu] 2 ctr .IP \[bu] 2 ofb .IP \[bu] 2 cbc .IP \[bu] 2 cfb .IP \[bu] 2 ecb .SS Misc .IP \[bu] 2 null .SS Complex Specifiers .PP Objects, when specified for creation by the TPM, have numerous algorithms to populate in the public data. Things like type, scheme and asymmetric details, key size, etc. Below is the general format for specifying this data: \f[V]::\f[R] .SS Type Specifiers .PP This portion of the complex algorithm specifier is required. The remaining scheme and symmetric details will default based on the type specified and the type of the object being created. .IP \[bu] 2 aes - Default AES: aes128 .IP \[bu] 2 aes128\f[V]\f[R] - 128 bit AES with optional mode (\f[I]ctr\f[R]|\f[I]ofb\f[R]|\f[I]cbc\f[R]|\f[I]cfb\f[R]|\f[I]ecb\f[R]). If mode is not specified, defaults to \f[I]null\f[R]. .IP \[bu] 2 aes192\f[V]\f[R] - Same as aes128\f[V]\f[R], except for a 192 bit key size. .IP \[bu] 2 aes256\f[V]\f[R] - Same as aes128\f[V]\f[R], except for a 256 bit key size. .IP \[bu] 2 sm4 - Default SM4: sm4128 .IP \[bu] 2 sm4128 or sm4_128 \f[V]\f[R] - 128 bit SM4 with optional mode (\f[I]ctr\f[R]|\f[I]ofb\f[R]|\f[I]cbc\f[R]|\f[I]cfb\f[R]|\f[I]ecb\f[R]). If mode is not specified, defaults to \f[I]null\f[R]. .IP \[bu] 2 ecc - Elliptical Curve, defaults to ecc256. .IP \[bu] 2 ecc192 or ecc_nist_p192 - 192 bit ECC NIST curve .IP \[bu] 2 ecc224 or ecc_nist_p224 - 224 bit ECC NIST curve .IP \[bu] 2 ecc256 or ecc_nist_p256 - 256 bit ECC NIST curve .IP \[bu] 2 ecc384 or ecc_nist_p384 - 384 bit ECC NIST curve .IP \[bu] 2 ecc521 or ecc_nist_p521 - 521 bit ECC NIST curve .IP \[bu] 2 ecc_sm2 or ecc_sm2_p256 - 256 bit SM2 curve .IP \[bu] 2 rsa - Default RSA: rsa2048 .IP \[bu] 2 rsa1024 - RSA with 1024 bit keysize. .IP \[bu] 2 rsa2048 - RSA with 2048 bit keysize. .IP \[bu] 2 rsa3072 - RSA with 3072 bit keysize. .IP \[bu] 2 rsa4096 - RSA with 4096 bit keysize. .SS Scheme Specifiers .PP Next, is an optional field, it can be skipped. .PP Schemes are usually \f[B]Signing Schemes\f[R] or \f[B]Asymmetric Encryption Schemes\f[R]. Most signing schemes take a hash algorithm directly following the signing scheme. If the hash algorithm is missing, it defaults to \f[I]sha256\f[R]. Some take no arguments, and some take multiple arguments. .SS Hash Optional Scheme Specifiers .PP These scheme specifiers are followed by a dash and a valid hash algorithm, For example: \f[V]oaep-sha256\f[R]. .IP \[bu] 2 oaep .IP \[bu] 2 ecdh .IP \[bu] 2 rsassa .IP \[bu] 2 rsapss .IP \[bu] 2 ecdsa .IP \[bu] 2 ecschnorr .IP \[bu] 2 sm2 .SS Multiple Option Scheme Specifiers .PP This scheme specifier is followed by a count (max size UINT16) then followed by a dash(-) and a valid hash algorithm. * ecdaa For example, ecdaa4-sha256. If no count is specified, it defaults to 4. .SS No Option Scheme Specifiers .PP This scheme specifier takes NO arguments. * rsaes .SS Symmetric Details Specifiers .PP This field is optional, and defaults based on the \f[I]type\f[R] of object being created and it\[cq]s attributes. Generally, any valid \f[B]Symmetric\f[R] specifier from the \f[B]Type Specifiers\f[R] list should work. If not specified, an asymmetric objects symmetric details defaults to \f[I]aes128cfb\f[R]. .SS Examples .SS Create an rsa2048 key with an rsaes asymmetric encryption scheme .PP \f[V]tpm2_create -C parent.ctx -G rsa2048:rsaes -u key.pub -r key.priv\f[R] .SS Create an ecc256 key with an ecdaa signing scheme with a count of 4 and sha384 hash .PP \f[V]/tpm2_create -C parent.ctx -G ecc256:ecdaa4-sha384 -u key.pub -r key.priv\f[R] cryptographic algorithms \f[I]ALGORITHM\f[R]. .SH COMMON OPTIONS .PP This collection of options are common to many programs and provide information that many users may expect. .IP \[bu] 2 \f[B]-h\f[R], \f[B]--help=[man|no-man]\f[R]: Display the tools manpage. By default, it attempts to invoke the manpager for the tool, however, on failure will output a short tool summary. This is the same behavior if the \[lq]man\[rq] option argument is specified, however if explicit \[lq]man\[rq] is requested, the tool will provide errors from man on stderr. If the \[lq]no-man\[rq] option if specified, or the manpager fails, the short options will be output to stdout. .RS 2 .PP To successfully use the manpages feature requires the manpages to be installed or on \f[I]MANPATH\f[R], See man(1) for more details. .RE .IP \[bu] 2 \f[B]-v\f[R], \f[B]--version\f[R]: Display version information for this tool, supported tctis and exit. .IP \[bu] 2 \f[B]-V\f[R], \f[B]--verbose\f[R]: Increase the information that the tool prints to the console during its execution. When using this option the file and line number are printed. .IP \[bu] 2 \f[B]-Q\f[R], \f[B]--quiet\f[R]: Silence normal tool output to stdout. .IP \[bu] 2 \f[B]-Z\f[R], \f[B]--enable-errata\f[R]: Enable the application of errata fixups. Useful if an errata fixup needs to be applied to commands sent to the TPM. Defining the environment TPM2TOOLS_ENABLE_ERRATA is equivalent. .IP \[bu] 2 \f[B]-R\f[R], \f[B]--autoflush\f[R]: Enable autoflush for transient objects created by the command. If a parent object is loaded from a context file also the transient parent object will be flushed. Autoflush can also be activated if the environment variable TPM2TOOLS_AUTOFLUSH is is set to yes or true. information many users may expect. .SH TCTI Configuration .PP The TCTI or \[lq]Transmission Interface\[rq] is the communication mechanism with the TPM. TCTIs can be changed for communication with TPMs across different mediums. .PP To control the TCTI, the tools respect: .IP "1." 3 The command line option \f[B]-T\f[R] or \f[B]--tcti\f[R] .IP "2." 3 The environment variable: \f[I]TPM2TOOLS_TCTI\f[R]. .PP \f[B]Note:\f[R] The command line option always overrides the environment variable. .PP The current known TCTIs are: .IP \[bu] 2 tabrmd - The resource manager, called tabrmd (https://github.com/tpm2-software/tpm2-abrmd). Note that tabrmd and abrmd as a tcti name are synonymous. .IP \[bu] 2 mssim - Typically used for communicating to the TPM software simulator. .IP \[bu] 2 device - Used when talking directly to a TPM device file. .IP \[bu] 2 none - Do not initalize a connection with the TPM. Some tools allow for off-tpm options and thus support not using a TCTI. Tools that do not support it will error when attempted to be used without a TCTI connection. Does not support \f[I]ANY\f[R] options and \f[I]MUST BE\f[R] presented as the exact text of \[lq]none\[rq]. .PP The arguments to either the command line option or the environment variable are in the form: .PP \f[V]:\f[R] .PP Specifying an empty string for either the \f[V]\f[R] or \f[V]\f[R] results in the default being used for that portion respectively. .SS TCTI Defaults .PP When a TCTI is not specified, the default TCTI is searched for using \f[I]dlopen(3)\f[R] semantics. The tools will search for \f[I]tabrmd\f[R], \f[I]device\f[R] and \f[I]mssim\f[R] TCTIs \f[B]IN THAT ORDER\f[R] and \f[B]USE THE FIRST ONE FOUND\f[R]. You can query what TCTI will be chosen as the default by using the \f[B]-v\f[R] option to print the version information. The \[lq]default-tcti\[rq] key-value pair will indicate which of the aforementioned TCTIs is the default. .SS Custom TCTIs .PP Any TCTI that implements the dynamic TCTI interface can be loaded. The tools internally use \f[I]dlopen(3)\f[R], and the raw \f[I]tcti-name\f[R] value is used for the lookup. Thus, this could be a path to the shared library, or a library name as understood by \f[I]dlopen(3)\f[R] semantics. .SH TCTI OPTIONS .PP This collection of options are used to configure the various known TCTI modules available: .IP \[bu] 2 \f[B]device\f[R]: For the device TCTI, the TPM character device file for use by the device TCTI can be specified. The default is \f[I]/dev/tpm0\f[R]. .RS 2 .PP Example: \f[B]-T device:/dev/tpm0\f[R] or \f[B]export \f[BI]TPM2TOOLS_TCTI\f[B]=\[lq]device:/dev/tpm0\[rq]\f[R] .RE .IP \[bu] 2 \f[B]mssim\f[R]: For the mssim TCTI, the domain name or IP address and port number used by the simulator can be specified. The default are 127.0.0.1 and 2321. .RS 2 .PP Example: \f[B]-T mssim:host=localhost,port=2321\f[R] or \f[B]export \f[BI]TPM2TOOLS_TCTI\f[B]=\[lq]mssim:host=localhost,port=2321\[rq]\f[R] .RE .IP \[bu] 2 \f[B]abrmd\f[R]: For the abrmd TCTI, the configuration string format is a series of simple key value pairs separated by a `,' character. Each key and value string are separated by a `=' character. .RS 2 .IP \[bu] 2 TCTI abrmd supports two keys: .RS 2 .IP "1." 3 `bus_name' : The name of the tabrmd service on the bus (a string). .IP "2." 3 `bus_type' : The type of the dbus instance (a string) limited to `session' and `system'. .RE .PP Specify the tabrmd tcti name and a config string of \f[V]bus_name=com.example.FooBar\f[R]: .IP .nf \f[C] \[rs]--tcti=tabrmd:bus_name=com.example.FooBar \f[R] .fi .PP Specify the default (abrmd) tcti and a config string of \f[V]bus_type=session\f[R]: .IP .nf \f[C] \[rs]--tcti:bus_type=session \f[R] .fi .PP \f[B]NOTE\f[R]: abrmd and tabrmd are synonymous. the various known TCTI modules. .RE .SH EXAMPLES .SS Example-1: Duplicate a key created with a policy that allows for duplication: .IP .nf \f[C] tpm2_startauthsession -S session.dat tpm2_policycommandcode -S session.dat -L policy.dat TPM2_CC_Duplicate tpm2_flushcontext session.dat tpm2_createprimary -C o -g sha256 -G rsa -c primary.ctxt tpm2_create -C primary.ctxt -g sha256 -G rsa -r key.prv -u key.pub -c key.ctxt \[rs] -L policy.dat -a \[dq]sensitivedataorigin|userwithauth|decrypt|sign\[dq] tpm2_createprimary -C o -g sha256 -G ecc -c new_parent.ctxt tpm2_startauthsession \[rs]--policy-session -S session.dat tpm2_policycommandcode -S session.dat -L policy.dat TPM2_CC_Duplicate tpm2_duplicate -C new_parent.ctxt -c key.ctxt -G null -p \[dq]session:session.dat\[dq] \[rs] -r duprv.bin -s seed.dat tpm2_flushcontext session.dat \f[R] .fi .SS Example-2: As an end-to-end example, the following will transfer an RSA key generated on \f[V]TPM-A\f[R] to \f[V]TPM-B\f[R] .SS On TPM-B .PP Create a parent object that will be used to wrap/transfer the key. .IP .nf \f[C] tpm2_createprimary -C o -g sha256 -G rsa -c primary.ctx tpm2_create -C primary.ctx -g sha256 -G rsa \[rs] -r new_parent.prv -u new_parent.pub \[rs] -a \[dq]restricted|sensitivedataorigin|decrypt|userwithauth\[dq] \f[R] .fi .PP Copy \f[V]new_parent.pub\f[R] to \f[V]TPM-A\f[R]. .SS On TPM-A .PP Create root object and auth policy allows duplication only .IP .nf \f[C] tpm2_createprimary -C o -g sha256 -G rsa -c primary.ctx tpm2_startauthsession -S session.dat tpm2_policycommandcode -S session.dat -L dpolicy.dat TPM2_CC_Duplicate tpm2_flushcontext session.dat rm session.dat \f[R] .fi .PP Generate an RSA keypair on TPM-A that will be duplicated (note the passphrase is `foo') .IP .nf \f[C] tpm2_create -C primary.ctx -g sha256 -G rsa -p foo -r key.prv \[rs] -u key.pub -L dpolicy.dat -a \[dq]sensitivedataorigin|userwithauth|decrypt|sign\[dq] tpm2_load -C primary.ctx -r key.prv -u key.pub -c key.ctx tpm2_readpublic -c key.ctx -o dup.pub \f[R] .fi .PP Test sign and encryption locally (so we can compare later that the same key was transferred). .IP .nf \f[C] echo \[dq]meet me at..\[dq] >file.txt tpm2_rsaencrypt -c key.ctx -o data.encrypted file.txt tpm2_sign -c key.ctx -g sha256 -f plain -p foo -o sign.raw file.txt \f[R] .fi .PP Compare the signature hash (we will use this later to confirm the key was transferred to TPM-B): .IP .nf \f[C] sha256sum sign.raw a1b4e3fbaa29e6e46d95cff498150b6b8e7d9fd21182622e8f5a3ddde257879e \f[R] .fi .PP Start an auth session and policy command to allow duplication .IP .nf \f[C] tpm2_startauthsession --policy-session -S session.dat tpm2_policycommandcode -S session.dat -L dpolicy.dat TPM2_CC_Duplicate \f[R] .fi .PP Load the new_parent.pub file transferred from \f[V]TPM-B\f[R] .IP .nf \f[C] tpm2_loadexternal -C o -u new_parent.pub -c new_parent.ctx \f[R] .fi .PP Start the duplication .IP .nf \f[C] tpm2_duplicate -C new_parent.ctx -c key.ctx -G null \[rs] -p \[dq]session:session.dat\[dq] -r dup.dpriv -s dup.seed \f[R] .fi .PP Copy the following files to TPM-B: * dup.pub * dup.dpriv * dup.seed * (optionally data.encrypted just to test decryption) .SS On TPM-B .PP Start an auth,policy session .IP .nf \f[C] tpm2_startauthsession --policy-session -S session.dat tpm2_policycommandcode -S session.dat -L dpolicy.dat TPM2_CC_Duplicate \f[R] .fi .PP Load the context we used to transfer .IP .nf \f[C] tpm2_flushcontext --transient-object tpm2_load -C primary.ctx -u new_parent.pub -r new_parent.prv -c new_parent.ctx \f[R] .fi .PP Import the duplicated context against the parent we used .IP .nf \f[C] tpm2_import -C new_parent.ctx -u dup.pub -i dup.dpriv \[rs] -r dup.prv -s dup.seed -L dpolicy.dat \f[R] .fi .PP Load the duplicated key context .IP .nf \f[C] tpm2_flushcontext --transient-object tpm2_load -C new_parent.ctx -u dup.pub -r dup.prv -c dup.ctx \f[R] .fi .PP Test the imported key matches .IP \[bu] 2 Sign .IP .nf \f[C] echo \[dq]meet me at..\[dq] >file.txt tpm2_sign -c dup.ctx -g sha256 -o sig.rss -p foo file.txt dd if=sig.rss of=sign.raw bs=1 skip=6 count=256 \f[R] .fi .PP Compare the signature file hash: .IP .nf \f[C] $ sha256sum sign.raw a1b4e3fbaa29e6e46d95cff498150b6b8e7d9fd21182622e8f5a3ddde257879e \f[R] .fi .IP \[bu] 2 Decryption .IP .nf \f[C] tpm2_flushcontext --transient-object tpm2_rsadecrypt -p foo -c dup.ctx -o data.ptext data.encrypted # cat data.ptext meet me at.. \f[R] .fi .SS Example-3: Exporting an OpenSSL RSA key for a remote TPM .PP To securely send an OpenSSL generated RSA key to a remote TPM such that only that remote TPM will be able to load it, and without exposing the private key to the host operating system on the remote machine: .IP \[bu] 2 On the destination TPM-B, create a primary context and read its public key, then send \f[V]primary.pub\f[R] to the source machine: .IP .nf \f[C] tpm2_createprimary -c primary.ctx tpm2_readpublic -c primary.ctx -o primary.pub \f[R] .fi .IP \[bu] 2 On the source machine create the RSA private key and wrap it for the destination TPM\[cq]s public key. Similar to \f[V]tpm2_makecredential\f[R], this step should not require a TPM. .IP .nf \f[C] openssl genrsa -out rsa.pem tpm2_duplicate -U primary.pub -G rsa -k rsa.pem -u rsa.pub -r rsa.dpriv -s rsa.seed \f[R] .fi .IP \[bu] 2 Send the \f[V]rsa.pub\f[R], \f[V]rsa.dpriv\f[R] and \f[V]rsa.seed\f[R] to the destination TPM-B and import the files, which will decrypt them using the \f[V]primary.ctx\f[R] to produce \f[V]rsa.priv\f[R], which can then be loaded and used as a TPM key: .IP .nf \f[C] tpm2_import -C primary.ctx -G rsa -i rsa.dpriv -s rsa.seed -u rsa.pub -r rsa.priv tpm2_load -C primary.ctx -c rsa.ctx -u rsa.pub -r rsa.priv \f[R] .fi .SH Returns .PP Tools can return any of the following codes: .IP \[bu] 2 0 - Success. .IP \[bu] 2 1 - General non-specific error. .IP \[bu] 2 2 - Options handling error. .IP \[bu] 2 3 - Authentication error. .IP \[bu] 2 4 - TCTI related error. .IP \[bu] 2 5 - Non supported scheme. Applicable to tpm2_testparams. .SH BUGS .PP Github Issues (https://github.com/tpm2-software/tpm2-tools/issues) .SH HELP .PP See the Mailing List (https://lists.linuxfoundation.org/mailman/listinfo/tpm2)